What was the main gun? Type, ammo, muzzle velocities, that sort of thing. So far I was able to find out just that it was a L/40 gun, ie shorter than that used in M-46/7/8 series, so was the Jpz 90 gun based on shortened US 90mm or was it an entirely new design? And sis it use US 90mm ammo or again something else?

I've never seen much more details.
You could ask the contact person for land warfare systems history at the manufacturer, though:
http://www.rheinmetall-detec.de/index.php?...3649&lang=3
He looks funny.

Some info from Wikipedia:
http://en.wikipedia.org/wiki/Kanonenjagdpanzer
And from the panzer museum in Munster:
http://www.panzermuseum.com/tank-destroyer-90mm.html

/Thord

The gun was indeed a shortened US 90. I don't remember the specs, but do recall a lower MV due to a shorter bbl. It didn't matter because the HEAT round was all that was in the basic load. I thought this curious because the HE and the WP rounds might have been quite useful. The penetration of the SHOT round was kinda iffey even in a full grown 90.

I got to fire one of these once. Good optics. Good controls. Crewmen used a throat mike that was much better than the mike on the CVC helmet.

Would that be enough for hunting BMP:s and other light vehicles?

300mm RHA penetration - good for them and more....

It was good enough for the T-55s of the time.

You really don't have any idea about BMP's protection levels, do you? This was one of the funniest for a long time...

The gun of the Kanonenjagdpanzer 4–5 was a Rheinmetall L/40,4, the main types of ammunition being HEAT and HESH, plus HE, smoke and illumination.
Barrel length: 4,91m
Weight of shell: 5,74kg HEAT and 7,45kg HESH
Muzzle velocity: 1145m/s HEAT and 795m/s HESH
Maximum effective range: 2000m
Ammunition laod: 51

Belgium also used the KanJPz 4-5, but their vehicles differed from the German ones by having the Renk transmission, final drives, suspension and tracks of the Marder, a SABCA FCS with an analogue computer and laser rangefinder, and Lyran flare launchers.

Yep I agree with Thomas Hoting
certainly about the belgium JPK's they build on the chassis of the marder and mutch loved by they crews for they handeling and comfort in the terrain. It wasn't just one time that a well placed belgium or german jpk could stop the advance of a compleet armoured unit in the nato exercises

here is a little site about the last belgium jpk in runnig condition
http://tankfreak.tripod.com/jpk/

Thanks for the information, gentlemen!

For the really curious in the early-mid 1970's Rheinmetal marketed a towed version of the 90mm L40 gun. This weapon had a large APU with a 1,500cc air-cooled Porsche engine at the end of the trail and the whole thing was designed to be driven a reasonable distance with a 3 man crew and 51 rounds aboard.

But horribly vulnerable to artillery, small arms, and dirty looks.

I do, but after editing my question several times it came out in worst possible way. (i was tired at the time)
What i was trying to ask was if that thing would still serve well if it wasn't expected to fight MBTs. As i understand it is pretty fast (well, reasonably fast) and presumably enough armour to be protected from those weapons BMP carries (excluding missiles).

Maintaining a dedicated "IFV killer" isn't a very good utilization of resources, not mention it would be easy game to the IFV's accompanying tanks.

All (?) of the Kanones got converted into Jaguar ATGM carriers anyway, which was probably the best use for the hulls.

2nd to that.

First: I agree that ATGM carrier is good choice if ability to kill pretty much anything in the field is desired. But still, if you do have those IFV killers in hand and you got crews to use them wouldn't they do the job? Also, if there are also friendly MBTs around, would those enemy tanks have time to shoot anything but MBTs?

Maybe maintaining and training for such an old design that has quite a norrow role wouldn´t be cost effective either. It´s a big tracked vehicle, consumes lots of fuel and spare parts and takes room in repair-shop facilities from better vehicles and can be used against lighter armour only and has to hide from tank guns and every ATGM and RPG there is AND can´t use superior weapon range to stand-off from the enemy but still is a big threat to everything there is on the battlefield (including MBT side armours) and so has to be killed immediately when seen.

Seems like a deathtrap to me.

Some became OP vehicles for artillery/mortar forward observers.

The original vehicle made sense when it was designed: a cheap tank destroyer to even numbers with the massive Red Horde ^™, a modern Hetzer. The missile armed version could engage enemy armor at long ranges while the Kanone covered the missile carriers (remember the SS-11 had a minimum range of at least 300m) and engaged enemy armor at closer ranges.

The 90mm gun became obsolete in the 70s and thus a number were converted into ATGM carriers, armed with better missiles which had both shorter flying times (17s for HOT, 21s for TOW vs 30s for SS-11) and a short minimum range (around 75m for both).

With the Cold War over, keeping such a vehicle wasn`t really justified. Austria, with a quite different doctrine and needs (but strong in defence over ofense) got a number of these to support their SK-105s, but they were also retired not long ago for more or less the same reasons (not to mention old age and rising maintenance costs)

despite that Belgium bought 80 of them in 1975....would have been interesting to use those in the eighties against T-64, T-72 or T-80 I suppose, alongside the ABLs mighty Leo1 tanks

Very true!

Even top notch tanks were not necessarily able to penetrate frontal armor of good opposing tanks in the 80's (or today) - while the flanks of all tanks are vulnerable.

The difference between a top notch MBT and a JPzK in the 80's was in daylight likely less important than tactical situation and crew quality. JPzK would have been used in the defense most often, and would therefore have been able to hit the flanks quite often.

I see two broad reasons to reject the suggestion of the Kanone as a dedicated IFV-Killer.

The first is over-specialization. This is the real bug-a-boo for almost all "heavy" AFVs. If it looks like a tank (tracks, armor and a gun), and sounds like a tank (goes "clankity-clank" and "boom"), it will get used like a tank. You just can't explain to a battlefield commander that he is "not supposed" to use a heavy AFV as a tank when he has a mission to accomplish that requires a tank. That was the major weakness of the US tank destroyers concept in WW2, and remains the major weakness of any non-tank heavy AFV.

The second is a poor match between gun and target. If you want to shoot up some IFVs, you are far better off with a high-velocity gun of smaller caliber, than a low- or mid-velocity gun of larger caliber. IFVs are usually smaller and more maneuverable than MBTs. They are particularly high-value battlefield targets prior to the infantry de-bussing, but are much lower-value targets after. So I would think you want a gun that shoots flat and fast at moderate- to long-range. Mid- to large-bore auto-cannons (25-40mm, maybe even 57mm?) would probably be the best IFV-killer weapons. A HEAT- or HESH-firing medium velocity 90mm gun seems like far too little "make sure to hit it" versus far too much "when you hit it punch through lots of armor" to me.

-Mark 1

Ummm,....




So 1145m/sec is considered medium velocity?

That's a rather respctable velocity, if you ask me, as in WW2 there were solid shot full caliber AP types that struggled to reach that mark,
and from guns of greater than an L40-ish caliber.
If 1145m/sec denotes medium velocity (average? higher end of the curve? lower end of the curve?),
then consider just how many medium velocity guns have proven themselves quite successful over the years, and at shooting vehicles, no less.

There are lot of IFV types whose autocannon don't reach that velocity with their various ammo types outside of APFSDS.

I'll agree that a HESH-firing gun like the 76mm on the Scorpion CVR(T),
or some of the various GIAT, Mecar, and CMI (Cockerill) shorter-barreled 90mm guns (HEAT being their primary anti armor round),
certainly are of the medium velocity category
(are there set parameters that denote exactly where the separation is between low, medium, and high velocity guns and ammo?)
but I don't know if I'd consider 1145m/sec as medium velocity.

I've also wondered of this gun (90mm L40 or whatever it is),
and I was taken aback when it was mentioned it actually mustered that velocity for its HEAT round,
especially when one considers that numerous other high perfomance guns of similar calliber (88-90mm) struggled to reach that velocity with any of their ammunition types.
(how does that round compare to the HEAT rounds available for the various US 90mm tank guns up thru that used in the M48 tank?)

If one takes into effect that the round is lighter than others by whatever percentage,
then certainly it makes sense that if it uses a similar propellant case, it should certainly have a higher velocity.
I just wouldn't have expected that performance from that 90mm gun, being only of about 40 calibers long
(compared to the 88/L71 of the King Tiger, for instance).

A few years ago, there was discussion on the TN AFV Techn forum about German development of 90mm APDS. It would seem likely that this ammo would have served both the JPz Kanone, which I saw still in use in 1978 by the Territorial Brigades, as well as the M48G, also still in use.

For the later 90mm guns used in the M48, the APC m.v. was 3000 fps and the HEAT was 4000 fps, or 914 m/s and 1219 m/s respectively. That was hot enough until special armors came into use.

double post

Didn't just struggle, didn't do it. Off hand I can't think of any that equaled 1145m/s, if for no other reason than the necessity to keep mv down so shot wouldn't shatter on impact.

I think you have that backward.

I love the JgPzK90 and JgPzRk with the SS-11 to death. Serious 60s cool........

Simon

In fact, both used compatible ammo!

In 1978 the Territorial Brigades were switching to the M48A2GA2, armed with the same gun as the Leopard 1.

But Kanone remained in service with some units in the AT role into the 1980s.

There were meant to be three vehicles in the series. The Jagdpanzer Kanone, Rackette and a turreted reconnaissance vehicle which was never produced. Does anybody have any drawings/pictures of that third vehicle? I've never seen any.

How was the barrel length measured? 40,4 x 90 mm = 3636 mm. Does the barrel length of 4910 mm include the breech ring and muzzle brake as well, i.e. the overall length of the gun (G.)? Would the 3636 mm be the length of rifling (B.)?

originally posted by cbo (the pictured gun is not the one in question right now, but illustrates the different methods of defining "barrel length") :

Brassey's "Artillery of the world" (1979) even tells abut 1181m/sec MV.

Did the gun designers of WW2 actually intentionally keep velocity low to avoid shattering the projectile upon impact,
or were they just not capable of achieving those high velocities with the propellant powder chemistry of that day and age?
Seems the APDS round of the 17-pdr got up there at a pretty good clip (1200-1300m/sec depending on your source).

Being composed primarily of tungsten in the penetrator (same as many solid-core AP types up thru even with the advent of DU), I fail to see that the gun makers of the day would've aimed to keep full-bore ammo velocities low so as to avoid shattering the projectile, not if they were actually aiming for higher velocities with the APDS principal.

More than likely, I just don't see that they knew any other methods to increase velocities that didn't cause considerable bore erosion (other than going with extremely long barrels like the 88L71 and 75L70 of German tank fame).

The suggestion that MV was intentionally kept down to avoid destroying the AP shot on impact?
No offense, but I just don't buy that (educate me, please?),
especially as it became apparent early enough in the War (WW2, in general) that heavy tank designs (Tiger, Panther, King Tiger, late KV's and early IS's) just couldn't be handled well enough head-on by lighter guns (those "medium velocity" gun types that armed so many AFVs right up thru the end of the War).

I know the earliest AP solid shot types were of steel alloys that were, hopefully, stronger than the armors they were hitting
(which is the only logical reason for keeping velocities down),
but with the advent of tungsten coring, is that the only reason we started to see MV increases then, because the shot could handle it?

I've seen cutaway drawings of WW2-era AP (full bore) types,
and the majority of them seemed to be fashioned around the notion of a large diameter generally blunt tip to smash thru armor by brute force,
whereas today's tungsten and DU AP types seem to favor the narrow tip APFSDS pattern, which seems more likely to function on the pierce-and-then-shard principle, rather than outright smash (kind of like comparing high velocity assault rifle ammo to larger-diameter, but lower velocity, submachine gun ammo...).

Aaaacckkk! We need to revive that caliber thread in the AFV tech forum also, because there was a difference between US and European methods of measuring, maybe even among Europeans and between army and navy ordnance. USN would be C in the chart, "plus the length of the screwbox". US Army is just C [effectively the same]. I think UK is the same. At least one of the European countries was not counting the chamber length??

DKTanker, I know memory is usually not to be trusted, but I did know the M48A3, had only a year as hands-on user of M60A1. But a glance at Hunnicutt, Patton, p.443 confirms: M318 [T33E7] shot 3000 and M431 HEAT 4000 fps. The M456 HEAT for the 105mm M68 lagged at 3850.

They tried with taper bore and subcalibre projectiles and succeeded, but at least the axis power hadn't enough tungsten to follow that path.
Germany could have killed Russian tanks easily with its taper-bore AT guns, but all tungsten had to be used for tools in the industry (ammunition as actually molten for that purpose).

Furthermore, they were able to achieve 1000+ m/sec MVs without these special techniques, but the barrel wear was excessive - again, not enough raw materials to get the very best barrel steel qualities (and driving band issues arose as well iirc).

Belgium's sector was hilly and wooded, so long ranges wouldn't have been the norm and speed and agility as well as a low silouette were desirable.

The HEAT I could buy, I thought you might have the AP too low, that is really a fairly low mv, pretty near what 105mm HEP is fired at. 4000 f/s= about 1200 m/s and 3000 f/s = about 900 m/s and 3850 f/s = about 1170 m/s. So you can see how I thought you had the values reversed with the 90mm HEAT being faster than 105mm HEAT and 90mm AP about the same as 105mm HEP.

The Jagdpanzer Kanone did in fact soldier on until the end of the Cold War. While it was replaced early on by missile firing versions in the brigade AT companies, it still served in the Territorial Heer, although in what capacity it is not entirely clear. The jager battalions and Heimatschutz regiments were nominally converted to M48A2G2 by the late 1980s, but it is entirely possible that some units (particularly the regiments) still used the Jagdpanzer. There were more than 500 Kanones nominally still in service in 1989, although some had been converted to armored artillery command posts.

My understanding was that its role was primarily for providing fire support in built up terrain and wooded areas, where the territorials would have been deployed. In those circumstances, it would provide some armored support to units that lacked any sort of tracked vehicle otherwise. Its role wouldn't have been limited to AT work -- it would likely have spent much of its time acting as an ersatz StuG. In an arena where 300m engagement range would have been long and flank shots common, it would have had some value, particularly to troops who had nothing else.

One of the major roles of the Territorials was to deny the WP the use of the urban areas, and the road network that ran through them. A second role would have been to operate against deep penetration raids by Soviet airmobile and airborne forces, and the Kanone was more than sufficient for shooting up BMDs. I don't think anyone evisaged them taking on a tank regiment of T-80s in a stand up fight.

Pat Callahan

correct and the JPK in the belgium army was intended as the mobile antitank gun in support off the infantery units so the 90mm was up to the job

This thread needs some pics and links.

http://www.battletanks.com/jagdpanzer_kanone.htm
http://www.panzerbaer.de/types/bw_kanjgpz_90-a.htm

Just wondering was there a competition before the JPK was accepted? What kind of prototypes were there? Could they have gone with an S-Tank-like vehicle with a traversable gun but with a long and low-angle (like 20 deg from horizontal) glacis?

I can only remember seeing one photograph of the Spaehpanzer. The turret was IIRC rounded, so likely cast rather than welded from flat plates, sort of like an M48 turret squashed down to a lower height. The front hull was noticeably shallower than usual (reclining driver?) so that the tank looked a bit lower than regular MBTs like Leopard I. The rear hull deck was raised, presumably to give enough room for the engine and the transmission. The gun looked shorter than the 90mm of M48, presumably the same 90mm L/40.4 as used by the Jagdpanzer Kanone. I think the photograph was in Wehrtechnik or a similar magazine, so if you have access to a library with copies from the late '50 to early '60s you might be able to find it.

The above is from my 40+ year old memories, so I'm not guaranteeing anything!

Hojutsuka

They didn't have a design competition AFAIK, IMHO because the German Army knew quite clearly what they wanted. They wanted a Jagdpanzer like the very successful WW II Hetzer and Jagdpanzer IV, but with a 90mm gun. They first tried mounting the 90mm gun on a modified HS30 chassis but it was not a success (the chassis was too small), so they decided to develop a new, larger chassis suitable for use with the 90mm gun as well as being the basis for a new IFV (which became the Marder) and a new reconnaissance tank (only prototype produced).

Prototypes were built by several different companies (mainly Henschel and Hanomag, though Mowag did build one example) and differed in some details. If you look at the photos posted by Homerr, the Jagdpanzer Kanone on display in front of a building is a prototype built by Henschel. It has 6 road wheels instead of the 5 on production Jagdpanzer Kanone, and narrower tracks.

The requirement to be able to work the breech and have enough room for gun depression and recoil when the gun is traversed means that a really low angle glacis cannot be used. The S tank gets away with it because its gun is fixed in relation to the hull.

Hojutsuka

A couple from APG...



Looks really snotty from this angle...I wouldn't care to have driven into it.